Apparatus for producing substantially clear ice bodies



Nov. 20, 1951 B. K. RoBERTs ETAL 2,575,892

APPARATUS FOR PRODUCING SUBSTANTIALLY CLEAR ICE BODIES Filed Feb. 28, 1949 2 SHEETS-SHEET l Vf Z0( @if Ei Hmm. I um!! I:

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APPARATUS FOR PRODUCING SUBSTANTIALLY CLEAR ICE BODIES Fi1ed Feb. 2s, 1949 2 SHEETS- SHEET 2 l/yh Patented Nov. 20, n 1951 APPARATUS FOR PRODUCING SUBSTAN- TIALLY CLEAR ICE BODIES Benjamin K. Roberts, Austin, Minn., and Clifford E. Enger, Los Angeles, Calif.; said Enger assignor to Roberts Products Incorporated, Austin, Minn., a corporation of Minnesota.

Application February 28, 1949, Serial No. 78,816

Z Claims.

This invention relates particularly to a method and apparatus for producing clear ice bodies.

In the freezing of artificial ice, it has been vfound to be a problem to freeze clear solid ice cubes which simulate the appearance of natural ice and thus meet with public acceptance much more readily than the cloudy cubes which are normally produced in conventional ice-making machines.

It is an object of our invention to provide a machine adapted to produce clear ice bodies.

It is another object to provide a method for producing clear ice bodies.

It is a further object to provide a plurality of intercommunicating open-topped molds mounted in a freezing compartment and adapted to have liquid circulated from one mold to the other and to produce circulation in the molds to carry off the air bubbles from the liquid being frozen and thus produce substantially clear ice bodies.

Itis still a further object to provide a series of open-topped molds with an inclined trough for carrying liquid from one mold to the other to produce a continuous cascade into each of the molds to circulate the water during the freezing of the liquid therein.

It is another object to provide a machine of the class described which is adapted for continuous thermostatically controlled operation whereby the clear ice after being frozen is released from the molds and carried from the freezing compartment to a dry storage location.

It is still another object to provide a clear ice cube producing machine having a thermostatic control system adapted to automatically operate the freezing and releasing cycles of said machine.

This releasing and flotation of the cubes from the freezing compartment to a storage compartment embodies substantially the same principles which were disclosed in a copending application filed in the name of Benjamin K. Roberts entitled Method for Producing Ice Bodies and Apparatus for Producing the Same and identified by the Serial No. 3605.

, The above and other objects and advantages of of our invention will more fully appear from the following description made in connection with the accompanying drawings wherein like reference characters refer to similar parts throughout the several views and in which;

Fig. 1 is a horizontal sectional view taken substantially along the line I--I of Fig. 2 and showingl the freezing compartment in top plan;

Fig. 2 is a vertical sectional view taken substantially along the line 2-2 of Fig. 1 and show- 2 ing a diagrammatic sketch of the thermostat control and the compressor unit and the electrical circuit therefor;

Fig. 3 `is a longitudinal vertical sectional view taken substantially along the line 3 3 of Fig. 1 and showing one bank of inclined mold containing troughs in side elevation; and

Fig. 4 is a perspective view showing the detail of a mold-containing tray.

As illustrated in the accompanying drawings, we provide an insulatedcasing 'I dening a freezing chamber which is divided by a central partition 'la into two separate compartments 8 and 9. A plurality of mold-containing troughs I Il are mounted in freezing compartments 8 and 9. In the form shown these troughs I0 extend longitufdinally of the compartments and are mounted in fixed relation on the side walls of each compartment 8 and 9 in vertically spaced relation one above the other, alternate troughs on each compartment wall being oppositely inclined.

The top row of troughs will be designated by the numeral II, the next row therebelow will be designated I2, and the next succeeding rows I3, I4, and I5 respectively. All four troughs in top row II slope in one direction, the troughs in row I2 slope in the other direction, and so on Adown through rows I3, I4, and I5.

Each trough has a plurality of cup shaped open-topped molds Il mounted in longitudinally spaced relation therein, as best shown in Fig. 1. The molds I'I are sunken into the bottom of the troughs I0, as best shown in Fig. 4, to provide a slight clearance between the top of the mold I'l and the top surface Illa of the trough bottom. The sides of the troughs I0 extend upwardly above the trough bottom to form liquid-confining walls IUb to retain the liquid therein during its flow downwardly through the trough. A partition Ic is mounted across the trough I0 between the liquid confining walls Ib between each adjacent pair of molds. This partition has a liquid flow notch IDd formed therein, the notches Ind of alternate partitions IIJc being alternately oil?- set from the longitudinal center line of the trough as best shown in Fig. 1 for purposes that will be brought out hereafter.

An angularly disposed upwardly sloping baille plate I8 is xed to the compartment walls below each of said troughs to guide the floating ice cubes upwardly in the compartments 8 and Sand prevent clogging thereof. A plurality of interconnection tubes I9 respectively interconnect the lower ends of the trough with the upper ends of thetroughs disposed therebelow to permit con-l tinuous ow of fluid from one trough to the other in each of the individual banks. In the forni shown a collection manifold [9a collects the discharge from three of the banks of troughs and discharges the same into a reservoir tank 34, which will be described in detail later. The fourth bank of troughs merely discharges directly into said reservoir tank 34. A refrigeration coil extends under each of the troughs and contacts the bottom portion of each of the molds, and each bank of troughs has its ownbranch of the coil 20, as is best shown in Figs. l, 2` and 3.

A conventional refrigeration. mechanism 2i sup- A thermostatic control mechanism. having the:

bulb 23 communicating with an. expansion bellows 24 is provided to actuate an electric switch' L the movable contact of switch upwardly to close the circuit through stationary contact 21. Both the pump 35 and the compressor motor 22 are connected in said circuit to be operated L upper portions of the inclined troughs in row Il to the lower ends thereof and from there downwardlyrthroughV interconnection conduits I9 into the respective trough-s in row l2 and so on down the .individual trough banks. As the liquid flows 25 which in the form shown is a single po-ledouble throw switch and is diagrammatically `illustrated in Fig.. 2. The bulb 23 is disposed within.. an air gap tube 23a to produce a slight lag in the thermostatic bellows 24 to temperaturesA within the freezing chamber. When thebellows 24 contracted by a low temperature within the chambe1,the shiftable element ofY theswitch 25 is in contact withstationary contact 29', and when the bellows 24 is expanded by a rise in temperature, the movable contact of switch 25 swings upwardly to close. the electric circuit through contact21. u

The solenoid Valve 28is electrically connected in series withthe circuit through contact 26, and a shut-oil switch 29 is interposed in said. circuit between the contact 25 and the solenoid. Said solenoid valve 28.`controls the ow of liquid from aliquid supply inlet 39 into'the freezing compartments 8 and 9 through the inlet conduit 3i and intercommunicating openings 32, and also controls the backflow of liquid through the conduit 3l to the drain 33, as best shown in Fig. 2. A reservoir tank. 34 is mounted in the bottom of compartment S and serves as a source of liquid supply for a pump 35, best shown in Fig. 2. The pum-p. 35 carries liquid from the reservoir tank 34v upwardly through a supply conduit 36 and discharges said liquid through the outlets 35a, 36h, and 36C which respectively supply the circulating water to the individual troughs is in the top row l I. This liquid is simultaneously discharged into all four banks of troughs to circulate liquidin the individual molds dur-ing the e freezing thereof to carry off any air bubbles and Operation 'IoV begin the freezing cycle, the` refrigeration" chamber is initially flooded by opening the solenoid. valve 28 to permit liquid to flow in through liquid supply inlet 39. Thereafter, the solenoid.

is deenergized, and the valve swings back into normal position to drain the two chambers B and 8' out'r through drainl 33. The machine is now ready'to go `into thermostatically controlled automatic operation. During the freezingV operation the-bellows24 is in expanded position to swing Vdown each ofy the inclined troughs, the alteri nately oi-se't notches 99d produce a cascading of theV water downwardly into each individual mold t disposed. therebelow to produce a whirling circulatory action in each of the molds. This circulatory action carries 01T the air in the liquid andl permits it to freeze in a solid substantially cloudless cube.. By ois-etting the liquid iiow notches llld from the `center line, the `liquid is introduced intol each individualV mold substantially adjacent the side wall thereof to produce a. tangential whirlpool action. in the respective molds. The bottom of each mold is concavely curved, as best shown in Fig. 4, to smoothly guide the circulating water around the bottom and upwardly back to the top of the mold and .thus carry off. the air.

When the temperature in the chamber reaches a predetermined low point, the liquid in each of the molds' will be completely frozen and the thermostatic control switch is set tol open the solenoid valve 28 and flood the chamber atthat time to overflow liquid out through ow chamber 31 and iiow outlet conduit 39. The solenoid valve 29 is, .normally in position to. permit free drainage from thechambers 8 and 9. out to drain 33 and topositively prevent flow of liquid through inlet conduit 39. When Vthe bellows 24 contracts toa predetermined point, the movable contact of switch 25 shuts off the compressor motor and pump and closes .the circuit through the solenoid valve 28 by making contact with stationary contact 23 and simultaneously opens the `valve and closes the drain to flood the chambers 8' and 9; The manuallyv operated shut-off switch 29. may be opened .to prevent flooding the. chamber when theV temperature drops therein, and cubes are merely stored until such time as switch 29 is again closed. This is desirable for storingcubes over a week-end or overnight, and as' soon as the switch 29 is closed, the machine is again on automatic operation to periodically discharge clear ice 'cubes into a storage location.

The. air. gap provided by tube 26 produces a time. lag between actual temperature reached within vthe freezing chamber and thetemperature reacting upon bulb 23. This permits relatively simple adjustment of the thermostatic mechanism andincreases the. eiiiciency cf its saidchambers have been drained, and the-switch;

The. molds Il arev left lledi 25 will again start the compressor motor 22 and pump 35 to repeat the cycle. With the switch 29 closed, the operation of the machine is continuous and automatic, but after switch 29 is open, the cubes will be frozen in each mold and merely stored therein until the switch 29 is again closed to put the machine into automatic operation.

The countersinking of the molds into suitable material which is a poor conductor of heat i:

and cold such as a heavy plastic material maintains a layer of frozen liquid across the top of each cube. This prevents a crust from freezing on the top and permits the circulating water to continuously carry oif the air in the molds.

It has been found that merely fiowing liquid over a series of open-topped molds will carry off most of the air bubbles in the molds and produce substantially clear ice cubes which are satisfactory for certain commercial uses; however, We have found that the best results are obtained by the method which specifically consists in cascading liquid into a liquid filled open-topped cup-shaped mold to produce a whirlpool circulatory action therein during the freezing operation.

It will be seen that we have provided and disclosed herein a novel and improved method for producing clear ice bodies, as well as the apparatus for producing the same. The apparatus is adapted to automatically freeze a plurality of clear ice cubes, and after freezing, to release the same from their individual molds and carry them by notation to a storage location. The

circulation of the water over the ice molds during the freezing operation carries off the air in the liquid and produces clear ice bodies in each of the molds. The thermostatic system operates continuously and automatically to alternately ood the chamber with liquid and carry oil? the frozen cubes therewith and after draining the chamber to freeze the liquid remaining in said molds and to circulate liquid through said molds during the freezing operation.

It will, oi' course, be understood that various changes may be made in the form, details, arrangement and proportions of the parts without departing from the scope of our invention.

What We claim is:

l. Mechanism for producing clear ice bodies comprising at least one inclined trough, a plurality of open-topped cup-shaped molds mounted in longitudinally spacedrelation in the bottom of said trough, and a plurality of spaced partitions transversely extending across said trough between the sides thereof and interposed between said molds to produce a water head above each mold and cascade the water into the respective molds to produce circulation therein during the freezing operation and carry off the air bubbles from the liquid being frozen in said molds and produce clear ice cubes therein.

2. Mechanism for producing clear ice cubes set forth in claim l and said partitions having laterally offset flow notches formed therein and disposed in substantial alignment with the side wall of said cup-shaped molds to respectively discharge liquid into said molds substantially tangentially of the sides thereof and produce a circulatory whirlpool action of said molds during the freezing operation and carry off the air bubbles from the liquid to produce clear ice cubes therein.

BENJAMIN K. ROBERTS. CLIFFORD E. ENGER".

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 706,510 Barrath Aug. 12, 1902 963,311 McCrary July 5, 1910 1,219,897 Althoff Mar. IZO, 1917 2,220,001 Potter Oct. 29, 1940 2,349,451 Motz May 23, 1944 2,443,203 Smith June 15, 1948 

